Related Patents have attorney docket numbers wakelley01, wakelley02, and wakelley03, wakelley04 and are listed below as Patent A, Patent B, Patent C and Patent D, respectively.
This patent is not federally sponsored.
Not applicable.
Many processes require a fluid make a transition from gaseous state to liquid and back, or from liquid to gaseous state and back. These include chemical separation, compression, water purification, and power generation. This is an energy intensive process, as simple methods for boiling and condensing both take large amounts of energy. However, the initial state (temperature) and final state of the fluid's are generally the same, or can be. A mechanism capable of boiling a fluid, then saving the energy by boiling a second fluid while liquefying the first allows the same energy to be used to gasify, liquefy, then gasify, or liquefy, gasify, and liquefy, is theoretically possible, as long as the energy quantities are matched.
Related Patents have attorney docket numbers wakelley01, wakelley02, and wakelley03, wakelley04 and are listed below as Patent A, Patent B, Patent C and Patent D, respectively.
Two devices are disclosed with similar purpose. One handles discrete quantities of fluid, the other handles continuous flow. Patent A, Patent B, Patent C, and Patent D in combination, can liquefy then gasify the outflow of a steam generator. The systems as is will recycle most of the water and heat. The devices described here use the same principles, but are specifically designed to be able to run as a closed system. This would meet a zero emission requirement. It would also allow steam generation plant to be operated economically in regions where water is scarce. A second class of devices is introduced, with the ability to cycle discrete quantities, and also can run as a fully enclosable system. An example application would be power generation from heated oil or liquid salts from a solar collection plant located in a desert. It could eliminate the need to pipe the heated fluid, as well as reduce the danger exposed when piping extremely hot materials.
Both devices are capable of cycling a fluid to and from gas state with a hot reservoir, or to and from liquid state with a cold reservoir. In addition, a small heat pump is included which can restore precise beginning conditions of the cold or hot reservoir.
Both devices are based on a combination of counter flow heat exchangers (Patent A) and reservoirs of heat or cold. (Technically a cold reservoir is more accurately described as having less heat).
The fluids should be matched in thermal capacity. With the same type of material in both chambers, this simply means an equal mass of fluid. It would simplify the system to have a reservoir that remains in liquid state, if a material is available that is liquid over the required temperature range.
If liquid is to be cycled to gas and back to liquid, a hot fluid reservoir is required.
If a gas (vapor) is to be cycled to liquid and back to gas, a cold fluid reservoir is required.
In either case, optimal efficiency will be when the reservoir temperatures are just above or just below the boiling point.
The reservoir temperature is independent of the temperature of the fluid to have phase changed. It simply must have enough heat or cold capacity to supply or exhaust the heat of the incoming fluid, and change of state.
Ideally the incoming liquid or vapor will also be near the boiling point.
Each reservoir has a piston to facilitate movement of the fluid. The piston is coupled to a second empty storage chamber, in a manner that pressure in each storage chambers are in balanced opposition.
A similar reverse arrangement is made on the incoming fluid side.
Typical fluids may be 100 to 1000 times denser than their vapor at STP. To avoid extreme pressures, the gas storage chamber must be larger than the liquid. For example, if the density multiple of a liquid to its vapor is about 600, a gas chamber three times the size of the liquid chamber would yield a density of 200Ă— density at STP.
Opposing pistons make fluid movement force independent of pressure. The vapor reservoirs must be larger in volume than the liquid reservoirs, but the area of the pistons must be the same, to equalize force. The reaction is begun by filling one side of counter flow heat exchanger with liquid and the other with vapor. Piston positions determine flow and direction of state exchange. If compression is required, a 5th, larger chamber of vapor will hold initial uncompressed target vapor. A simple valve switches connection of the target side of counter floe heat exchanger between the large uncompressed chamber and the small compressed target chamber.
Pressure in the system depends on temperature for all gases (vapors). Consider an application which first drops vapor temperature to 90 degrees, with a boiling point of 75. The cold liquid reservoir must be 60 degrees or colder to insure complete phase change.
Phase change is achieved via controlled flow on each side through the heat exchanger in opposite directions. The heat exchanger should be oriented vertically, liquid phases at bottom.
It is sufficient to insure complete phase change if the fluid being liquefied is not allowed to rise into the heat exchanger, but moved at a speed to keep liquid phase level at the bottom end of the heat exchanger, and to insure the liquid level of the other fluid being gasified, is maintained near the top of the heat exchanger. This insures heat flow from gas phase to liquid phase throughout the heat exchanger.
Completion of the level monitoring phase is done when target fluid is completely phase changed.
At this point, the expected benefit has occurred or will occur on the opposite phase change. Reverse phase change can begin immediately.
Reverse phase change requires flow directions from storage chambers of each fluid is reversed. The level monitoring control is the same, but liquid levels are reversed between target and reservoir sides.
At this point the benefit has been realized.
Benefits might include a) drastic reduction of a gas's (vapor's) volume without doing work of compression, separation of a mixed vapor into its components by boiling point, removal of contaminants from a liquid (e.g. distilled water).
The last step is to restore initial reservoir temperature, which will have moved toward the boiling point. Counter flow heat exchangers can approach 100% but not achieve it. To the extent heat was incompletely switched between the fluids, the heat reservoir temperature needs to be adjusted.
The hot reservoir can be adjusted by pumping heat from the liquid outflow into the hot reservoir. This is a very small adjustment relative to the energy of vaporization or condensation. Ideal setup will have intake and outtake as near boiling point as possible.
Adjusting the cold reservoir uses the same strategy, but instead pumps from the cold liquid reservoir into the hot fluid vapor outflow. Again, temperature differences will be small, so heat pump has a small amount of energy to move, compared to heat of Vaporization.
After operation of the heat pump, vapor based or thermoelectric device, the system is restored to its initial state and ready for the cycle to repeat.
A continuous flow system requires two sets of discrete devices operated on opposite phases, or the components of Patent A, Patent B, Patent C and Patent D connected as a Counter Flow Heat Exchanger coupled to a Fluid Pressure Ladder to make a Thermal Pressure Multiplier (
To make a closed fluid system, fluid tight connection must be made between all components, such as Turbine and Heat Exchanger's intake, and Heat Exchanger's outtake and the reservoir, and the Reservoir must be enclosed as well. This is sufficient for enclosed fluid system, but also requires temperatures remain stable, within an operating range.
For a Vapor to Liquid to Vapor system, the necessary component to run fully encapsulated is to add a second Heat Pump connecting the reservoir to the pre-heated (by recycled heat) fluid. Since the middle of the temperature gap will include a phase change, this is actually a very small temperature rise. The Heat Pump does not need to be 100% efficient, as any added energy will end up in the pre-heated fluid, pre-heating it further.
For a Liquid to Vapor to Liquid system, the same can be done by pumping heat from a liquid outtake into a hot vapor reservoir. Again, heat pump inefficiency is also pumped to the hot Reservoirs, where the energy is desired. (So no energy is lost).
For a closed Vapor system, such as a steam generator, it may be more convenient to use ambient air to stabilize (cool) the reservoir temperature. This would reduce energy efficiency by the amount of heat lost, but would be a cheaper and much simpler system, requiring no heat pump.
Operation of continuous flow system requires only equal inflow and outflow, a rate allowing heat to be nearly completely transferred, and a series of heat exchangers sufficient to perform complete temperature exchange.
Operation of the discrete quantity device is by fluid level. The liquid fluid level is risen by lifting that dual piston until fluid is at the desired point in the vertically oriented counter flow heat exchanger. The fluid level on the gas side is similarly maintained at a physically lower point in the counter flower, by moving dual pistons down. In the case of liquefying a large volume, the pressure the gas is normally under keeps the counter flow heat exchanger filled with vapor exposed to temperatures which will cause condensation. It will take some time to condense enough fluid to reach the desired fluid level. As the vapor liquefies, the pressure drops to near zero, or volume drops to near zero under constant pressure.
Energy used by the system is 1) sufficient energy for movement of the mass of the fluids and friction and 2) sufficient to power a small heat pump to stabilize the Reservoir Temperature. Thermoelectric devices are ideal for the heat pump device. The much larger heat energy of vaporization (and energy given by condensation) are conserved and reused.